This proposal is directed at the human health hazards from exposure to polychlorinated biphenyls (PCBs) and their virulently toxic impurities, polychlorinated dibenzofurans (PCDFs). It integrates a study of these chemicals in humans living near a dumpsite with studies in laboratory mammals and in a neurological model species, the marine gastropod Aplysia. New chemical analytical technology will be applied throughout to observe more than 100 common congeners of PCBs and PCDFs in human body fluids and animal tissue. It will also be used to monitor engineering-scale extraction and destruction of these compounds by super-critical fluid technology, ambient-temperature and thermophilic bacteria, and permeability studies of typical geological landfill materials. Nine projects are proposed: I) an epidemiologic study of a native American community living on a reservation (Akwesasne) adjacent to a Superfund- designated landfill contaminated with PCBs and PCDFs. Levels of contaminants in fish and wildlife consumed by pregnant and nursing mothers will be correlated with levels in body fluids, including breast milk, and with levels in urine and feces in infants; II) a study of pre- and postnatal exposure of rat pups to PCBs and PCDFs, correlating pregnancy outcomes, tests of development and alterations in brain neurochemistry with body burden; III) a morphologic study of livers from the animals in part II, with investigation using the Albany high voltage electron microscope to elucidate relative toxicity and ultrastructural changes associated with exposure; IV) a study of exposure of an invertebrate, Aplysia, to PCBs and PCDFs, correlating bioaccumulation with several measures of behavior, brain chemistry and brain physiology; V) a study of anaerobic biodegradation of PCBs in soils; VI) a study of anaerobic thermophilic digestion of PCBs; VII) a study of the effectiveness of supercritical extraction and supercritical oxidation to remove and/or destroy these contaminants; VIII) a study of the migration of these contaminants through the soils of Akwesasne; and IX) support of most of the above projects for analysis for PCBs, PCDFs and polychlorinated dibenzodioxins (PCDDs), together with the development and validation of quantitation of these substances in urine and feces, particularly from infants' diapers, as a method of population screening. While this study is inspired by a particular population which traditionally has a greater dependence upon local flora and fauna than most, and a particular hazardous waste site which contaminates this region, the results should be are relevant to many populations and many sites.